Reading Scale

Chapter 2: Performing Mensuration and Calculation

Lesson 1: Reading the Scale

• Introduction to the concept of measurements and scales.

Pretest

• A brief evaluation to assess prior knowledge on mensuration and calculation techniques.

Activities

• Engaging hands-on activities to reinforce learning and practical understanding towards the subject matter of mensuration and calculation.

Problem Scenarios

Problem 1: Airplane Hangar Issue

• Scenario: A new airplane cannot fit in the hangar due to discrepancies in measurements.

• Blueprint Height: 19.5 meters.

• Actual Height: 20.2 meters due to manufacturing error.

• Guide Questions:

  1. What is the problem in the scenario?

  2. What could have caused this issue?

  3. How can this situation be fixed?

Problem 2: Collapsed Pedestrian Bridge

• Scenario: A bridge collapses during construction because of measurement errors in material.

• Blueprint Span: 12 meters.

• Beams Length: 6 meters (with a needed total length of 6.1 meters each).

• Guide Questions:

  1. What is the problem in the scenario?

  2. What could have caused this issue?

  3. How can this situation be fixed?

Problem 3: Refrigerator Installation Issue

• Scenario: A refrigerator is too wide to fit between kitchen cabinet spaces despite measurements showing it should fit.

• Advertised Width: 85 centimeters.

• Available Cabinet Space: 88 centimeters, with total wall space of 2.7 meters.

• Guide Questions:

  1. What is the problem in the scenario?

  2. What could have caused this issue?

  3. How can this situation be fixed?

Problem 4: Film Set Chariot Size Issue

• Scenario: A chariot replica is too large to fit through the palace doors.

• Blueprint Door Width: 3.5 meters.

• Chariot Width: 3.2 meters as per blueprints.

• Guide Questions:

  1. What is the problem in the scenario?

  2. What could have caused this issue?

  3. How can this situation be fixed?

Problem 5: Theater Costume Fit Issue

• Scenario: A suit of armor does not fit the lead actor.

• Script Description: Arm pieces at 70 centimeters, helmet circumference at 80 centimeters.

• Actor's Measurements: 75 cm for arm length and 82 cm for head circumference.

• Guide Questions:

  1. What is the problem in the scenario?

  2. What could have caused this issue?

  3. How can this situation be fixed?

Reading Instruments

Types of Instruments:

• Volt-Ohm-Milliammeter (Multimeter):

  • Measures voltage, resistance, and current.

• Tachometer:

  • Measures engine RPM (Revolutions per Minute).

• Oscilloscope:

  • Plots electrical signals over time.

• Ampere meter:

  • Used to measure current.

Volt-Ohm-Milliammeter (Multimeter) Details

Reading the Dial Setting

• Voltage Measurement:

  • Indicate DC or AC current type via symbols (straight line for DC, squiggly for AC).

  • DC voltage indicated as V- or DCV; AC voltage indicated as V~ or ACV.

• Current Measurement Settings:

  • Alternating Current: A- or ACA.

  • Direct Current: A-- or DCA.

• Resistance Measurement:

  • Measured in Ohms (symbol: Ω).

Troubleshooting Settings

• Use settings for continuity, diode, and frequency measurements.

• Confirm connections and ports properly for accurate testing.

Output of an Analog Multimeter

Scale Readings

• Resistance Measurement: Use the omega scale; adjust according to position.

• Voltage Readings: Take careful consideration of scale ranges.

• Decibel Scale: Requires practice for accuracy in measuring voltage ratios.

Tachometer Overview

• Functionality: Measures the rotation speed of machinery.

• Scale Interpretation: Understand safe operating ranges highlighted in green (safe zone) and red (danger zone).

Oscilloscope Functionality

• Purpose: Diagnostic tool to monitor electrical signal changes over time to identify faults in circuits.

Ampere Meter Functionality

• Description: Measures the flow of electric currents in amperes (A).

Final Activity

• Application of learning outcomes through practical exercises related to the measurements and instruments discussed.